Fire door and shutter.



P. L. SAINO, D. M. LYNCH, W. P. DUNBAR & J. H. WEATHERFORD.

FIRE DOOR AND SHUTTER.

APPLICATION FILED FEB. 11, 1907.

Patented Jan. 24, 1911.

4 SHBETSSHEET 1.

0 o o o c 00 9 I 1 9 X f F. L. SAINO, D. M. LYNCH, W. F. DUNBAR & J. H.WEATHERFORD.

FIRE DOOR AND SHUTTER.

APPLIOATION FILED FEB 11, 1907.

Patented J an. 24-, 1911.

4 BBBETEPBHEET 2. v

F. L/SAINO, D. M. LYNGH, W. P. DUNBAR & J. H. WEATHERFORD.

' PIREDOOR AND SHUTTER.

APPLICATION FILED FEB. 11, 190..

Patented Jan. 24, 1911.

4 SHEETS-SHEET 3.

%Z/I/EJJEJ. l/vrf/vra/r n M w 7 F. L. SAINO, D. M. LYNCH, W. F. DUNBAR &J. H. WBATHERPORD.

FIRE DOOR AND SHUTTER.

APPLICATION FILED FEB.11, 1901.

Patented .1111124, 1911.

4 SHEETSSHEET 4..

. N n. 1 1. 1 i d uNrrE STATES PATENT QFFlQE.

'ELIX L. SAINO, DOSSEY M; LYNCH, WILLIAM F. DUNEAE, Ann JOSEPH I-I.WEATHER- EoEn, 0F MEMPHIS, TENNESSEE, ASSIGNORS T0 SAINO FIRE noon ANDSHUTTER COMPANY, or MEMPHIS, TENNESSEE, A CQRPORATION or TENNESSEE.

- FIRE DOOR ANl) SHUTTER.

To all whom it may concern:

Be it known that we, FELIX L.. SAI o, DossEY- M. LYNCH, VVILLIAM F.DUNEAR, and JOSEPH H. l/VEATHEREORD, citizens of theUnited States,residing at Memphis, Shelby county State of Tennessee, have inventedcertain-new and useful Improvements in F irellpors and Shutters,- ofwhich,

the followingis a s ecification.

Our invention re ates to certain new and useful improvements in firedoors and shut ters, and has especial reference to improve;

ments in those which are made of sheet metal.

The objects of our invention are to so improve the construction ofthedoor or.

shutter; first ;that it will withstand a severe amount of heat withoutdisintegrat ing; second; that it will not'warp or twist out of shapeunder severe test; third; that 1t Wlll transmit a minimum amount ofheat;

fourth; to improve generally the construction and details! We accomplishthese objects as will be more fully set forth hereinafter in thedrawings, specification. and claims, in which, however, we have confinedourselves to the construction of the door, and omitted allreference tothe shutter.

In the drawings -F igure 1 is a face view of the door showing as itappears when closed, and showing the hangers, stay-roller andbinderswhich hold it in place, as they Fig. 1.

are used ordinarily. Fig. 2 is a partial back elevation and section onthe line IIII Figs. 3 and 7', looking in the direction of the arrow.This and the remaining drawings are on a very much larger scale thanthat of 3 1s a sectional elevation on the.

Fi' I line III-ill of Fig. 2 looking from the right toward the left of Fig. 2. Fig. l is a section on the line IV--lV of Figs. 5 and (3 looking.down. Fig. is a sectional elevation on the line VV of Figs. 4i and 6looking in the direction of the arrows. Fig. 6 is a partial frontelevation showing the upper left hand corner of the door shown inFig. 1. F ig. "T is a section of the door on the line VIl-Vll of Fig. 1looking down. 8 is a section on the line VHF-VIII of Fig. l looltin inthe direction of the arrow. Fig. 9 iragznentary'section on the lineIX--lXof Big. 10 looking down. Fig. 10 is on the line X-X of Fig. 1looking in 5 irection of the arrow.

Specification of Letters Patent. Patented Jan, 24, 191 Application filedFebruary 11, 1907. Serial No. 356, 891.

Referring nowto the drawings in which like parts are designated by'thesame nupeculiar construction.

the door. disposed Figs. 6 and 7. The several widths are rivof a singlerigid sheet.

in the present door, of four sections 3&3",

3, etc, which, i f corrugated, preferably havetheir corrugationshorizontally disposed.

one overiapping'the upper edge of the next, and coupledv looselytogether by the loose rivets 4, which are put through the-vertical slots5 in the overlap; orother eflective mechanical device which holds theseedges in alinement,lmt' which permits the overlap to. be diminished by asliding motion. Thus a vertically expansible rear wall is formed. InFigs. 2 and 3 it will be seen that one or two of the corru gations areflattened to permit easy sliding of the overlap when corrugated sheetsare used. i

The rear portion of the door'on the side away from the fire is composedof the refractory. sheet 2 of asbestos or similar material, attached tothe inner surface of the" metal sections 3 3, 'etc., by means of rivets3 and large washers 7, or by other ef material to the rear sheet 3 and.in contact therewith at intervals throughout its surface.

sheets 2 and 3, are riveted together by rivets S and f) at the fouredges oi the door only.- .atswill be seen by reference to Figs. 6, 7, Sand 10 the rivets 8 at the top and bottom edges are provided withspacing collars or washers 10, which serve to hold the front -1 moralein all views, the door consists funda-flmentallyf a front 1 of sheetmetal, an inmade of one or more 1 of sheet metal ofcommer vertical, aswill be more clearlyseen by'reference to eted-rigidly together to formthe equivalent The metal portion 3' ofthe rear is com 1 posed of two ormore sections of sheet metal;

As will be seen by referenceto Figs. 2 and 3 they. areplaced with thelower edge of the" We may use $01116 fcctive means of riveting the morefragile;

The front 1 and the rear, composed of 60* ported and stifiened byrigidly apart to form an air chamber orchannel extending throughout thesurface of the door, By reference to Figs. 6 and 8 it will be seen thatthe top of the channel .is made to open u ward and outward toward thefire side 0 the door by making the front sheet shorter than the rear atthe top. Likewise Fig. 10 shows the rear wall shorter than the front atthe bottom of the door, thus allowing the free entrance of air from therear or cooler side of the door, as shown by the bent arrows. When ahigh temperature is maintained outside the front sheet, heating saidsheet to a red color, the air in this channel or chamber becomes heatedby intimate contact therewith, and, since the air in the room to beprotected is at a much lower temperature than that on the inte rior ofthe door, a flue-action or draft will be caused by the continuousdisplacement of the lighter heated air by the cooler. This fresh supplyof cooler air, by absorbing heat from'the front sheet during its ascent,allows an increase in the duration and temperature of the exposure towhich the door may be subjected without melting the metal. I

When corrugated metal, horizontally disposed, is used for sections ofthe'rear metal sheet 3, 3 3 etc., a series of dead air pockets orchannels are formed between the door. This also provides corrugations ofsaid sections and the sheet of refractory material 2, thus reducing to aminimum the radiation of heat through the a transverse stiffnessthroughout the rear surface of the door.

The stiffening frame is formed of stiles or side framing consisting-ofchannels 12 and bars 11 and 14 (observe Figs. 4, 5 and 7); of top rail,consisting of channel 31 (observe Fig. 8) and of bottom rail, angle 32(observe Fig. 10). These are riveted or or otherwise rigidly fastenedeach is composed of expansively connected sections or parts that thedoor as a whole may expand in all directions. Inharrow doors'it iscommercially desirable to omit the sectional formation of-the top andbottom rails, since the Warping and twisting of relatively shortchannelsand angles is inconsiderable even when subjected to severe difference intemperature between the side edges of the same piece of metal.

Portions of the side framing are'protected from severe heat at the sideedges of the door by the overlapping of the side edges of the frontmetal sheet 1 and the sheet sf refractory material interposed, as, willbe seen by Fig. 77 If theffront sheet b'e corrugated, it is flattened atthe side edges for this purpose, anda portion of the flattened marginal,e'tlgeis bent backward at right angles to fer-m an L in cross sectionwhich extends as far'backas the rear wall of the stiffening framerqThesheet of'refractory material2"is.bent to conform to the inner surface ofthis L, and the edges of both sheets l and 2 are retained by rivets 18,as may be seen by reference to Fig. 4. Be tween the sheet of refractorymaterial 2 and 'the remaining portion of the aforesaid flattenedmarginal edge of the front sheet 1,

close in the corner of the l. and fiatwise to fractory sheet 2andmetal-sections 3, 3 3,

' etc. Being flat against the hot metal sheet at its front and at oneedge. and against'the asbestos. sheet in the rear, and having oily onenarrow edge as a cooling surface, his bar attains almost the sametemperature as thefront sheet and, therefore, expands and contracts withit without tearing the rivet holes of rivets 9.

'The stiifening channels 12 are formed by.

bendin a narrow piece of sheet metal longitudinal ly to form a squarecornered U in cross-section with one leg longer than the other. Theextra length of this longer leg is then turned outward as indicated b inFig/ L In assembling, these channe s are inverted and placed with theportion 12 between the side edges of the rear metal sections 3*, '3", 3,etc., and the asbestossheet 2, the shorter side coming against 'theinner surface of the L of the asbestos sheet. These channels 12, beingnarrower across the U than the width of the. flat straps 1i,

permit the same rivets 9 which pass through the front sheet 1 and barsll, to pass through the leg 12 of channel 12, and through the side edgesof the rear sections 3*, 3*, 3", etc;

which are superposed. Thus a vertical box-- like air passage or flue ofconsiderable dimensions is formed by the channel 12 and asbestos sheet2, the metal walls of which are shielded from severe heat by theasbestos and the fire-proof wall against which the door placed inservice. Since this stiti'ening channel is protected and is, therefore,practically cold, there will be a consider-- able dilference between itslength and the length of the fiat strap 11 to which it is riveted byrivets 9, when the door is subjected to heat on. the exposed side. Topre which are long enough to overlap a considrrable distaiicc.

It will be noted that there arejtour sections also, 3, 3, 3", etc, inthe rear metal sheet 3-5 of this particular door; and that they areloosely coupled together at bottom and top edges respectively. Thusthere are as many overlapping or telescopingsections in channel 12asthcre are sections 3, 3, 3, etc., of the rear metal sheet 3.

"Special attention is now called to the manner of riveting togetherthese several pieces. The rivets 9 pass completely through the frontmetal sheet 1, metal strap 11, asbestos sheet 2, portion of channel 12and edge of a section of rear metal sheet '3 and binds all of themrigidly together at the .points of riveting. But by close inspection ofFigs. Nos. 1 and 2 it will be seen that the spacing of rivets 9 isnotuniform, but that they are placed in segregated groups; each ofwhich. is made. up of a few uniformly spaced rivets. Theoretically,these metal sections of rear sheet 3 and channels 12 should be rivetedto the front sheet 1 and strap 11 at one part only with a single rivetat the middle of the side edge of each section; but in practice it isfound that the extent of riveting employed does not so greatly interferewith the unequal expansion and contraction of the several parts that the.va'i -ping of the door as a whole, and the tearing of the rivet holesand the rivets, are observed. The number of rivets employed ,materiallyincreases the strength of the whole structure when distributed as doscribed. Thus it is seen that the vertical rear metal wall 3; andconsequently the bulging away from thewall 'at the middle of thesides ofthe door will not occur as with rigid stiffening members of one piece,

' channel (obs riye Figs. 4, 5 and 7.l

or of several pieces so constructed as to he the expansive equivalent.of a single piece.

.l.he'channels 12 are stiffened and held in ,alinemcnt by placing astiff bar of metal 14,

which extends ,the full length of the door, within the channel andretaining it against vthev back, or ,the bottom of the U, by theinsertion of ;several bolts 13 throu 'h the 13 pass across in, front ofbar 14 and hold ,it closely in place but do not prevent the werticalsliding of the several sections of channel 12 along thebar. Bolts 13 areso inserted at the? overlap orKf telescope. of the joints, and at btherpoints nearby,.that.they

prevent both thebendingof the barv and the buckling of the, overlappingjoints in the channel, but allow the. individual expansion:

Bolts" of each section, and their separation from each other. As beforementioned they also pass through the L shaped edges of the front sheet 1and refractory sheet 2, and fulfil the additional service of retainingthem against'the stiffening frame and preventing the buckling andtwisting of the thin edge as angle iron usually does under unequalheating of the edges. Theholes for these bolts 13 are slottedlongitudinally in the outer metal sheet 1 and refractory sheet 2 and inthe overlapping portion of an adjacent channel section. Bar 14: may bebent at its upper end as shown at 15 in Fig. 5 and abut against bar 11to give the corners rigidity and to allow a fastening such as a wrappingof a portion of upper channel 31, or other means resorted to forsecuring it at one point in its length.

* By referring to Fig. 8 it will'be seen that the upper edge of the rearmetal section 3 extends above the front sheet 1 and asbestos" sheet 2and is bent outward toward the front of the door, and then a portion'ofthis edge doubled back, thus forming the doubled-back portion 35,.and riveted or bolted at its loweredge to the front and back walls ofthe door by the rivets 8 pass ing completely through all parts of thedoor at the top. This channel rail 31 may be made'in' sections and bereinforced an aliningstrip as used'with the side channels 12 or not, asthe width of the door opening requires. The upper edge of this channel31, being exposed to the heat, may attain a higher temperature than thelower edge, and therefore provision must be made in doors of unusualwidth. for thcwa'rping or distortion produced by a great incqu'.-1lit vof temperatures of the opposite edges of the same channel. However, theheat largely deflected away from this exposed surface by the deflectedupward current of air before mentioned, and by the. proximity of thetrack 17. i

The lower rail or angle 32 of the stiffening frame is shown in Fig. 10.As here shown, it is an angle with vertical leg riveted to the loweredge of she'et fliI a rnl-witli "the other leg extendinghorizontallybackward tothe rear face of the-dryer. "By refrence to Fig.1 1t will beseen that this angle 1s formed 1n sectlons wh ch byoverlapping and telescoping freely;,a;llow individual. ex-

pansion and contraction,ofqthe several sections; These sections-as inthechannelj-ll -may have a trotighor c h'annel formed at the rear edgefor the rec eption-of a. stiffening bar in. a mariner sim lar totheifstiffening bars 14 in the side channels 12. This part of the frame,the angle 32, has a very small portionexposed directly to the action ofthe flames as it rests directly upon the sill of brick or concrete 23,and is thereby protected fromthe heat from below; therefore thesectional format-ion is employed in wide doors only.

By reference to Figs. 1 and 8 it will be seen that the door is supportedin the usual manner by the hangers 16 which are of the I usual form, andtherefore not specially described. These hangers run on a flat track 17,fastened to the wall 18 by bolts 19and spacing cones or brackets 20 inthe usual manner.

21 is a metal bar fastened to the inner sideof the hanger 16, having thearm 22 to the wall by means of the track.

25 is the ordinary form of stay-roller, and 26 the stay-roll strip whichis fastened to the face. of the door, and formed with a wedge 26 asshown. in the plan Fig. 9, in order that the door may be jammed closelyto the wall when the momentum of the door in closing jams this wedgebehind the stayroller 25. p

In: Fig. '1, the ordinary form of front binders are shown at 27 27 28 ofFigs. 1 and 7 isa rear binder hoop which consists of a hook-shaped pieceof metal, the back of which is countersunk in the! wall 18' andfastened-to' the same by the bolts 29. This binder hook is adapted to engage anopening 30 through the boxshaped side of the stiffening frame and. holdsthe door when shut firmly against the.

wall.

33 is a spacer bar or washer of metalbetween the front and back at thepointwhere the hanger bolts 34 pass through the door to prevent drawingof the front and back together at that point (observe Fig. 8).

The door is so hung that under ordinary circumstances'the flame willcome against the front sheet 1 or face of the door.

the sections of the cooler back and those between thc. cooler section ofchannel 12. But, being fastened at the side edges to the ends of'thesections 3 3, etc., which are cooler and, therefore, expand much lessthan sheet 1, the front sheet buckles and bulges outward to compensatefor the difference ,in horizontal expansion, tending to become'alongidudinal section of a large corrugated cylindrical surface. Thisbulging, however,

j spacers 10.

This sheet when heated expands in a vertical di rection rapidly,stretching the joints between is restricted at the top and bottom of thedoor by the rails 31 and 32 of the stiffening frame which are riveted byrivets 8 to the bottom of each corrugation, the expansion of sheetlbeing used up by the collapsing accordion-motion of the corrugations ofthe red-hot metal sheet 1. The middle portion, however, not having thisrestraint does bulge outwardly, the two hulgings, horizontal andvertical, producing a bellying outward or a spherical bulging at thecenter of sheet 1. By this distortion a larger air space is formedbetween the front and back, and asuction of air is produced, which airwhen heated passes out at the top, and sets in motion the coolingcurrent before mentioned.

It will be observed that the" cool air is drawn from the side of thedoor away from the fire, entering the door at the bottom, and isdischarged as heated airat the top of the door on the fire side only.

The refactory material, drasbestos 2, being held intact by itsfasteningsto the rear sheet 3, is comparatively undisturbed by changesin temperature of the face of the door, and serves to prevent kanyconsiderable amount of heat being radiatedthrough the door.

It will be noted that the rear section 3, 3", etc., could be fastenedhorizontally across its middle to the front sheet in a manner and bottomsimilar to that usedat the top e. by use of rivets 8- and of the door,'5.

As will be noted the door shown in drawings is formed of sheets ofcorrugated metal disposed with the corrugations, at right angles to eachother. It will be readily seen, that the sheets of which the dooriscomposed may be simply flat sheets of metal which, provided they arespacedapart-at the top and bottom, and are properly put'together topermit the vertical separation of the-rear sections, and bulging of thefront sheet at the center, will accomplish practically everything thatthe corrugated sheets do. The corrugated sheets make a stiffer andbetter door, and for that reason should be preferred in ordinarypractice. While-,we have confined our description to a door, it .will bereadily seen that by substituting the word shutter for door ,thisdescription will apply to a shutter as'well."

Having fully described our invention, what we claim and desiretosecure-by Letters Patent in the United States is "'1. In a device ofthe kind described, the combination with a front wall of sheet metal,

and a c ompbsite back wall of non-combustible materials divided intoseparate overla ping sections, and means for spacing t ewalls apart toform an air channel; of means for connecting the sections togetherwhereby a sliding movement of the overlap is al 1 lowed transversely tothe edges to compenll l ' material and being divided into independenttheir edges.

. of said form an air space;'the stantially in a single piece, the backwall besaid sectionsgbeing composed of sheet metal wall, a stiffening.lapping sections, [posed of sheet metal and refractory mate- .rialfastened together, means for holding the front and back walls apart toform an air tion withja front wall, and a back wall dies'aeos sate forthe unequal expansion of the front and back walls. I I

2. In a fire door or shutter or the like, consisting of two parallelwalls spaced apart to front wall being subing composed of sheet metaland refractory overlapping sections with-means for rigidly .attaclnngaportion-of each section to the expansile other portionsof the sec- 3. Afire door. or shutter having a front wall, a back wall of overlappingsections,

and sheet refractor material fastened together, means for olding saidfront and back walls apart to form air space, and means for-rigidlyfastening said sectionsto the front wall throughout only a portion of 4.A fire door or shutter having a front frame, a back wallof over saidsections being comspace, and means for independently fastening eachsection to the frame whereby a .diffcrence betweenjtheexpansions of thesection and frame is "allowed. I

5. In a fire door or shutter, the combinaided into sections whoseedgesoverlap, of means for connecting the overlapping edges sections togetherpermitting cxpanl s1 re movement transversely to the adjoining edges ofthe section's.

. 6..In a fire door 01' shutter, the combination with a front wallsubstantially in one piece, and a back wall of metal composed of aplurality of overlapping sections,of a plurality of loose rivetsinserted through slotted 1 holes in the overlap ing edges to'expansiblyl and means for fasten fastenings distributed throughout only a or.-

connect together an aline the said. sections, ing the said walls to- Igelher.

7. In a' fire door 01' shutter, the combination with a front wallsubstantially in one I piece, of a back wall of sheet metal compris-- iing a plurality of separate sections, and a a plurality of fasteningsdistributed throughi out only a portion of the surface ofeach sec- Ition for rigidly front wall while allowing sliding motions of otherportions of the sections with respect to the adjacent portions of thefront wall to compensate for a diiference in expansion.

8. In a fire door or shutter, the combination with a frame, a front wallattached thereto, and a back wall composed of a plu-' rality of separatesections, of a pluralityof tion of the surface ofeach section for'rigidly,

section :and the main securing that portion to the securing that portionto the frame while allowing sliding-motions of other portions of thesection with respect-to'the adjacent portions of the frame to compensatefor a difference in expansion.

9. In a fire door or shutter, the combina tion with a stiffening frame,a front wall attached thereto, a back wall comprising a plurality ofseparate sections, spacing said walls apart to form an" air space, of aplurality of fastenin s distributed throughout only a portion 0 eachsection for rigidly securing that portion to the and means for framewhile allowing sliding motions of otherv portions of the sectionwithrespect to the adjacent portions of the frame to compensate for adifference in expansion. I 10. In a fire door or shutter, thecombination with the body portion of sheet metal and refractorymaterial, and metallic stiffening members attached thereto, the edges ofthe refractory material overlapping on the memher to protect the saidstifi'ening members from severe heat.

1 1. In a fire door or shutter, the combine tion with a main bodyportion of sheet metal and refractory of sections attachedindependegtly"thereto, said sections being protected from severe heat byportions of the sheet metal and refractory material.

12. In a fire door or shutter, the combinetion with anon-combustible'main body portion, of metallic stiffening-memberscomposed of a-iplurality of sections attached thereto, means forstiflenin the said sections, means Io fastening each of said member ofthe main body portion whereby a diflerenceb'etween the expansions of thebody portion is allowed; said stiffening members being insu lated fromthe heat of the common member by an interposed layer of refractorymaterial.

13. In a fire door or shutter the combination with the body partthereof, and stiffening members composed of a plurality of sections ofmetal attached thereto; of a stiff bar slidably secured in commpn to thesevr individually material, of metallic stiffening members composed of aplurality into alinement.

sections to a common eral sections of a member for stiffeninginto meansfor fastening each of'thejsaid secscctions and for reintions toracorresponding sectionof the back wall whereby a difference between theexpansionsof the section of back wall and: sec tion 10f. stiffeningmember is allowed; said heat of the front wall by 1 opening thereinstifi'ening'members being insulated from the an interposed layer ofrefractory material.

15. The combination ofa fireproof wall having a door opening therein,and a rear binder hook attached to said wall, w'1th a door consisting ofmetal sheets, a stifi'emng frame for sald door projecting backward fromsaid sheets, the said frame having an adapted to be engaged by the saidhook.

' 16. A fire door or shutter, having a tele 'jscopically expansiblestiffening frame built into and forming a component part of the mainbody ortion thereof. 17. In a re door or shutter, the combination with amain body portion, of a stifi'ening member divided into sections, andmeans for stiflening into alinement the several sections of a member.

18. In a non combustible fire door or j-shutter, the combination with amain body portion, of stiffening members attached thereto composed of aplurality of sections overlapping at adjoining and freely sliding ends;said sections being alined by their in ,portion, of stiffening membersattached thereto composed of a plurality of sections lapping atadjoining and freely sliding ends; said sections being alined by theirindependent fastenings to a common member of the main body portion, andby projecting fastenings of one inserted through slots in the lappingportion of the other.

In a non-combustible fire door or shutter, the combination with a mainbody portion, of stiffening members attached thereto composed of aplurality of sections with adjoining ends free to slide; said sectionsbeing alined by their independent fastenings to the said main bodyportion and by a stifi} ening barslidably secured in common to the saidsections.

In a noncombustible fire door or shutter,the combination with a mainbody por tion,,of stiffening members attached thereto composed of aplurality of sectionseach of hollow.- substantially U shaped crosssectionv overlapping a'tiadjoining and freely sliding ends; said'sectionsjbeing alined by the over:v

partially inclosing the comple-,

lap ofhone mentary form of the other, and by projecting fastenings ofoneinserted through slots in theoverlapping portion of the other.

w 22.1 131 a non-combustible fire'door or shutlet; the combination witha main body portion, of stiffening members attached thereto composed ofa plurality of sections each partially inclosing the comof hollowsubstantially U shaped cross section overlapping at adjoining and freelysliding ends; said sections being al ned by the overlap of one partiallyinclosing the complementary form of the other, and by a stiffening barslidably secured in common to the'said sections.

23. In a non-combustible fire door or shutrality of overlapping sectionsattached there to, of a plurality of projecting fastenings of onesection inserted through longitudinally slotted holes in the overlappingportion of the other section to connect each section expansibly to theadjoining section.

24. In a non-combustible fire door or shutter, the combination with amain body portion, stifiening members composed of a plurality ofsections attached thereto, and means for alining and stiffening saidsections, of means for fastening each of said sections to a commonmember of the main body portion whereby a difference between theexpansions of the section and the main body portion is allowed.

25. In a non-combustible fire door or shutter, the combination with amain body. portion, stiffening members composed of a plurality ofsections attached thereto, and means for alining and stifiening'saidsections, of a plurality of fastenin'gs-distributed throughout only aportion of the edge of each section for rigidly securing that portion tothe main body portion while allowing sliding motions of other portionsof the section with respect to the adjacent portions of the main bodyportion to compensate for a difference in expansion.

26. In a fire door or shutter, the combination with front and back wallsof non-combustible materials, of metallic stiffening members composedofa plurality of sections attached thereto, and means for' alining andstifiening said sections, .of -means for fastening each section to acorresponding section of the back wall whereby a difference between theexpansions of the section of back wall and the section of stiffeningmemher is allowed.

j 27. .In a fire door or shutter, the combination with front and backwalls, stifi'ening members composed of a plurality of sections attachedthereto, and means for alining and stiffening said sections; of aplurality of fastenings distributed throughout only a portion oftheedg'e of each section for ri idly securing that portion to :1.corresponding portion of a section of the back wall while allowingsliding motions of other portions of the section of stifiening memberwith respect to the adjacent portions of the section of back wall tocompensate for a difference in expansions.

28. In a non-combustible fire door or shutnames to this specification,in the presence ter, the combination Withe main body porof-twosubscribing Witnesses.

tion, stiffening members composed of a plu-' FELIX L SAINO rality ofhollow sections in alinement at- DOSSEY LYNCH 5 cached thereto, ofsplurality of fastenings I ,ILLIAM DUNE to confine a stlfi'ening metalbar Within the v w 1 7 several hollow sections in c ommony which JObLPHEATHERFORD' v are thereby slidably secured to the .said \Vitnesses:

metal bar andstifiened into alinement. F. M; FLANERY, 10 In testimonywhereof we have signed our H. H. HIGBEE.

